And while Obama’s request on Syria is sure to drown out the debate over the budget, immigration and Edward Snowden’s whereabouts, it’s a special blow to Gillibrand, whose cause could be made even harder if Congress becomes less interested in confronting the Pentagon at a time of international conflict.

“Clearly, momentum is someplace else right now,” said Oklahoma Sen. Jim Inhofe, the Armed Services Committee’s senior Republican and a leading critic of both Gillibrand’s efforts and Obama’s call for U.S. airstrikes in Syria.

There’s little doubt Gillibrand’s amendment will still get a vote. Senate Majority Leader Harry Reid has promised one when the defense authorization bill comes to the floor. But the schedule on that must-pass legislation — never quite clear before Syria rocketed to the front burner — now stands in even greater limbo, and senior aides say it could even be punted past Christmas.

“I am expecting it later rather than sooner,” said a Senate Democratic leadership aide. Added another staffer who expected Reid to hold off until the end of the year: “You don’t waste a must-pass vehicle where you don’t need to.”

While Gillibrand and some of her allies say the delay will be good for their whip operations — more time means exposing more members to victims’ stories and the Pentagon’s lax enforcement — there’s equal measures of worry that undecided senators and the Defense Department are eager to let this debate fall from the radar given the touchy politics of voting either for or against the wishes of rape victims.

And even the military says the issue has fallen by the wayside in the past amid war. Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, acknowledged as much during testimony earlier this summer, saying, “I think I took my eye off the ball a bit in the commands that I had” on the sexual assault problem during the Afghanistan and Iraq wars.

“If the U.S. starts lobbing any kind of firepower in the issue, [our lobbying] is going to the back burner,” said Paula Coughlin, a former Navy lieutenant and whistleblower in past high-profile sexual assault cases.

The August recess has no doubt taken some of the air out of the issue after a heated summer debate that split Senate Democrats — with Gillibrand vying for votes against Armed Services Chairman Carl Levin (D-Mich.) and Sen. Claire McCaskill (D-Mo.) — and the additional political wildcard of 2016 GOP hopefuls Paul and Cruz signing on to the Gillibrand effort.

But the competing sides haven’t gone silent either.

Protect Our Defenders, a victim-advocacy group, has delivered more than 260 letters to senators. The group’s staff and officers had more than a dozen meetings with senators and their aides in Washington and back home in their states — many of them undecided — over the August break. Advocates say they’ll also be bolstered by several high-profile sexual assault cases moving now through the military’s opaque justice system, including the Naval Academy superintendent’s pending decision on whether to court-martial three former football players and the Fort Bragg trial later this month of Army Brig. Gen. Jeffery A. Sinclair, a rare event for such a high-ranking officer accused of assaulting a female subordinate.

McCaskill, who was blindsided earlier this summer by a Protect Our Defenders ad attacking her position in her home-state paper, the St. Louis Post-Dispatch, also went on offense publishing an op-ed in USA Today with California Democratic Rep. Loretta Sanchez, herself a victim of sexual assault. The two Democrats went directly after Gillibrand. “We view this as a risky approach for victims — one that would increase the risk of retaliation, weaken our ability to hold commanders accountable and lead to fewer prosecutions,” they wrote.